Evaluation On The Potential Of Geothermal Resource In Tianjin

As a kind of natural, clear and green energy, geothermal resources in the Tianjin area are rich. The development and utilization of geothermal resources became a large-scale industrial activity, which is more and more important in the Tianjin’s economy. It has brought not only economic and social benefits but also promoted the grade of Tianjin city in the world.The main used geothermal reservoirs in the Tianjin area are the Neocene sandstones of Minghuazhen and Guantaozu formations, the Ordovician and Cambrian carbonate formations and the Proterozoic Wumishan carbonate formations. Based on the general tectonic geological characteristics in North-China, this study constructed a geological model for the geothermal resources in the Tianjin area. The spatial distribution of different reservoirs were analyzed.Taking the plain are in the south of Ninhe Baodi Fault as the 8700 km2 target zone for the geothermal resources evaluation, this study used the geothermal reservoir method in calculating the energy storage and static fluid thermal resources as well as the amount of the recyclable geothermal energy for five typical reservoirs. As a result,the total geothermal energy in the Tianjin area is 175.02×1019J, which is equivalent to585.83×108T standard coal, and the total recyclable geothermal energy is14.98×1019J,which is equal to 50.93×108T standard coal.According to the current status of geothermal resources utilization in Tianjin, the sustainable development potential of the geothermal energy is evaluated using the fuzzy comprehensive evaluation method. The modulus of development potential,injecting rate, mean falling rate of groundwater level, decrease of temperature and rationality of pumping wells distribution were considered in the evaluation program.Reasonable policies for sustainable utilization of geothermal resources were proposed based on this evaluation results.